• Journal of Biosystems Engineering
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• v.34 no.3
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• pp.161-166
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• 2009

This study was conducted to investigate the growth characteristics of cherry tomatoes in greenhouse using far infrared heating system. The far infrared greenhouse heating systems were installed in two ways on the greenhouse side wall and at the greenhouse ceiling. The heating characteristics of far infrared heating system were analyzed by investigating the heating load, internal temperature, energy consumption, growth characteristics and quality evaluation. The results were compared with heated air heating system using kerosene. The results showed that tomatoes grown in the greenhouse with the far infrared heating system had relatively better plant height, leaf length, leaf width, stem diameter than ones from the greenhouse with hot air heating system and both heating methods had no significant difference on Cherry tomato sugar contents. At the same time, the far infrared heating system reduced heating cost from 34.5 to 41.4% on comparing with hot air heating system.

• Journal of the Korean Society of Costume
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• v.64 no.7
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• pp.156-171
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• 2014

This study attempted to comprehend the usage of the modular system in fields through literature review and objective research, as well as analysis of its expression characteristics in fashion. It tried to provide inspiring visual data for the fashion design of the modular system. After analyzing architecture and product-related books, Internet data and advanced research, the four expression characteristics of the modular system were obtained. Firstly, the formative expression characteristics of the modular system in fashion were simplicity, extensibility, variability and diversity. Secondly, of the formative expression characteristics expressed in modern fashion, simplicity (30%) was the highest, followed by extensibility (27%), diversity (22%) and variability (21%). Thirdly, simple silhouette and structure were used to express simplicity, usually simple geometric figures. In contrast, extensibility was expressed through the expansion and exaggeration of the area, length and volume of the clothes. In terms of variability, the typical characteristics of modules were reflected. For diversity, heterogeneous materials were used, and informality was expressed.

• Journal of Aerospace System Engineering
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• v.8 no.3
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• pp.47-54
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• 2014

This is a research on the method of how to improve stall characteristics for the small general aviation airplanes to meet the FAR part 23 requirements. This research is based on the experience of certification flight tests of KC-100 airplane for Korea type certification. KAS/FAR Part 23.201/203 are the stall characteristics requirements. 23.201 requires to show the stable stalling tendency of the wings level stall and 23.203 requires to show the stable stalling tendency of stall characteristics during turning flight. In this paper, the stall characteristics requirements, improvement methods and flight test experience of KC-100 airplane for type certification.

• Journal of the Korean Society of Visualization
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• v.16 no.2
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• pp.7-15
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• 2018

The fluid-flow characteristics of flue-gas-recirculation (FGR) system can have a significant effect on system efficiency of a sintering plant. The flow characteristics in the system were investigated. A sintering plant with FGR system was modeled. Numerical visualization was performed and flow characteristics were analyzed. Characteristics of the flow distribution of the branch ducts, the inflow of air into the recirculating hood, and the flow in the hood were discussed. Based on the results three suggestions were proposed: (1) distribution of branch duct flowrate upstream, (2) installation of external air ducts in the hood, and (3) installation of baffles at the hood corners. The suggestions were tested numerical and experimental visualization methods. The suggestions were effective and confirmed to be applicable to the actual sinter plant.

• Korean Institute of Interior Design Journal
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• v.14 no.5 s.52
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• pp.44-51
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• 2005

This study focuses 'Korean characteristics' in architectural interior design. In this study, some Korean characteristics was extracted by analysing traditional Korean spaces and as well as by considering the architectural interior spaces which are designed with Korean character since 1970. This paper started with differenciating the elements and principles that consist of space, and then classified the elements into 8 categories such as Spatial system, Enclosure system, Circulation system, Material system, Furnishing system, Light, Color, Context which are analysing frames. As a conclusion, the concepts of Korean characteristics are extracted and suggested as design concept with Korean characteristics by analysing the contents of each category. These concepts were presented with simple diagrams and supporting cases were also presented in this paper. The design concepts of 'Korean characteristics' are classified in the 25 concepts: Holonic composition, Transitional space, Hierarchy by floor level, Gradation of privacy, Changeability, Various central yards, Space with opened edges, Gray space, Continuity of space, Translucent wall, Folding-lifting wall, Skeleton, Abstract facet, Path as a message, Mild light, Multii-layered vista, Fluidity, framed scenery, Serial view, Interpenetrating Space, Harmony with nature, Organic interrelationship, Complementary Dual Structure, Temporal change of space, Hierarchical order.

• Progress in Superconductivity and Cryogenics
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• v.17 no.1
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• pp.32-35
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• 2015

Many kinds of high temperature superconducting (HTS) devices are being developed due to its several advantages. In particular, the advantages of HTS devices are maximized under the DC condition. A line commutated converter (LCC) type high voltage direct current (HVDC) transmission system requires large capacity of DC reactors to protect the converters from faults. However, conventional DC reactor made of copper causes a lot of electrical losses. Thus, it is being attempted to apply the HTS DC reactor to an HVDC transmission system. The authors have developed a 8 mH class HTS DC reactor and a model-sized LCC type HVDC system. The HTS DC reactor was operated to analyze its operational characteristics in connection with the HVDC system. The voltage at both ends of the HTS DC reactor was measured to investigate the stability of the reactor. The voltages and currents at the AC and DC side of the system were measured to confirm the influence of the HTS DC reactor on the system. Two 5 mH copper DC reactors were connected to the HVDC system and investigated to compare the operational characteristics. In this paper, the operational characteristics of the HVDC system with the HTS DC reactor according to firing angle are described. The voltage and current characteristics of the system according to the types of DC reactors and harmonic characteristics are analyzed. Through the results, the applicability of an HTS DC reactor in an HVDC system is confirmed.

• The Korean Journal of Community Living Science
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• v.24 no.3
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• pp.391-397
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• 2013

This study was conducted to define the characteristics of the fan according to the bed depth of rough rice for the silo used in South Korea. In this study, the characteristics like air flow resistance and air flow rate of the fan were investigated for an independent blowing system with 1 fan and the serial blowing system with 2 fans. In the experiment, the depth of rough rice was determined by 0, 1, 2, 3.2 and 4.5 m for an independent blowing system and the depth of rough rice was 4.5 m for the serial blowing system. The air flow resistances of the blowing fan and the suction fan in an independent blowing system were 55 mmAq and 88 mmAq respectively. In addition, the air flow resistance of the serial blowing system was 61% lower than the blowing fan and 28% lower than the suction fan of the independent blowing system. The air flow rates of the blowing fan and the suction fan in the serial blowing system were 516 $m^3/min$, 570 $m^3/min$, respectively. The former was 22% higher than the blowing fan while the latter was 29% higher than the suction fan in the independence blowing system. In other words, the serial blowing system was superior to the independent blowing system in blowing characteristics because the air flow rate was lower and air flow resistance was higher than the independent blowing system. However, the fan power consumption of the serial blowing system was more than 100% comparing with the independent blowing system.

• Korean Institute of Interior Design Journal
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• v.15 no.2 s.55
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• pp.166-173
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• 2006

Architectural color has been preserved the multiple characteristics reflected the change of social value criteria and technical development. Especially, the change of technical paradigm has led to variation from simple and fixed color system, as through the considerable change of architect's subject thinking, favored and symbolic system. Now, architectural color has also been revealed as the timely, moving, behavioral and existent color by anthropolatric thinking system. Therefore, it could be transformed expressive system reflected from abstract-pictorial characteristics, from the fixed to non-determining system, constructive to non-constructive system, context to expressive system, reasonal to emotional system, respectively. So, the range of architectural color has been extended as a element in reinforced the planned concept of the architect beyond the past decorated and symbolic color scope. As thereinafter, future's architectural color could be expected to concrete to the public-friendly relation system, developed widely to the system for reinforcing the concept not introduction of meaningless, fragmental and instinct color through the relational adaptation with design concept.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.24 no.6
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• pp.449-457
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• 2011

Effect of pump combinations on the vacuum characteristics of vacuum system was simulated for optimum design of system. In this investigation, the feasibility of modelling mechanism for VacSimMulti simulator was proposed. Simulation results of various pumping combinations showed the possibilities and reliabilities of simulation for the performance of vacuum system in specific semiconductor processing. Simulation of roughing pump presented the expected pumping behaviors based on commercial specifications of employed pumps. Application of booster pump exhibited the high pumping efficiency for middle vacuum range. Combinations of optimum backing pump for diffusion and turbo vacuum system were obtained. And, the predictable characteristics of process application of both simulated systems were also acquired.

• Journal of the korean Society of Automotive Engineers
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• v.12 no.3
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• pp.21-29
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• 1990

Equipments of passenger cars with modern technologies are gaining their importance. Related with such developments, the four-wheel steering system (4WS) was introduced recently to a few passenger cars in the market. The most important research goal on this new steering system is improvement of active safety, in other words, improvement of handling characteristics of vehicle stability and maneuverability. This paper presents a computer-based study about the effects of 4WS system on the vehicle handling characteristics. A simple bicycle model of 2 d.o.f. is used for the development of four wheel control algorithms of 4WS system, and the rear wheel control strategies are applied to a complex vehicle model of 16 d.o.f. for simulation of selected ISO-driving tests. The 4WS systems, which reduce the sideslip angle at the mass center of vehicle to almost zero, show much improved handling characteristics compared to that of the conventional 2WS system. These 4WS systems, however, result in vehicles with eigen-steer characteristics of extreme understeer behaviour.